Robot systems comprising one or more robots are widely utilized in different fields of technology in order to carry out work that cannot be efficiently carried out by humans or which is impossible to carry out for humans. For complex tasks, such as, e.g., the manufacturing of an aircraft or spacecraft, many different working operations have to be carried out, so that a robot having multiple different tools for carrying out the different working operations or being able to move through the working environment to get the respective tool required for a particular working operation has to be provided. However, in particular in working environments with a limited space, such as inside the fuselage of an aircraft or spacecraft, there may not be sufficient room for a big robot having multiple tools or moving through the working environment. Further, big robots having multiple tools may be relatively inflexible with regard to an adaptation to different working operations, and in limited space environments big robots moving through the working environment may pose a danger to human technicians working alongside the robot.
Nevertheless, it is strongly desired to make use of robot systems also in such environments, because otherwise, in fields such as aircraft or spacecraft manufacturing requiring highly skilled technicians, these technicians must also perform plenty of simple tasks, such as, e.g., walking out of and into the fuselage in order to get or return a required tool, searching for and getting appropriate material or preparing surfaces for a subsequent working step, as well as a lot of unergonomic tasks, such as, e.g., overhead work with heavy tools or other tasks requiring ergonomically unfavourable body postures, such as bent-over or kneeling positions, in particular when working on areas which are difficult to access. Also, the working environment itself may sometimes be uncomfortable due to, e.g., very high or very low temperatures, high humidity, intensive noise and/or vibrations. One example is a space environment, in which humans are operating under conditions very different from the ground, and low gravity and protective suits makes it difficult for the humans to control and carry out body movement. All of the above puts high demands on a technician to perform high quality tasks with a required high precision, in particular when a heavy tool must be used.